bigleman

iTrader: (4)

I'm looking into getting a custom turbo setup made for my auto. What would be the best way to get the exhaust to the turbo, I have seen the design that takes the y pipe and bends it into a U to send it back up in the engin bay, but I think b/c I have an auto, the tranny takes up too much room and there is no where to put the pipe... well I guess 2 pipes...

Anyone have any ideas? I wasnt really planning on putting down 4 grand for a kit (not ever gonna happen).
So am I gonna have to get an exhaust manifold custom made or will the bent y-pipe work?

Oh, I ran through all the stickies and didn't see anything about this, but if I did miss something could you send me in the right direction? Thanks.

bigleman

iTrader: (4)

I just saw some pictures of a "forward y-pipe" and that looks like a good idea too, would that be the best way to go?

1MAX2NV

iTrader: (5)

If you don't plan on putting down $4K for a turbo kit, a custom turbo setup will set you back even more. If you don't know how to weld, you are going to pay $$$ for labor.

bigleman

iTrader: (4)

i just need the pipes made, i can install the rest no problem

slimer

iTrader: (13)

since you live in SC, why dont you ask shadow or mishap to see theirs?

Redmax

iTrader: (20)

Sorry, but I really don't think this is a project for you. After you spend the money on the turbo kit, you will need to build that Auto because you will smoke the tranny within 2 days so Your budget doesn't have it ini it

Bags

iTrader: (3)

bigleman

iTrader: (4)

2 days, you sure about that? I'm not worried about it going out in 10-12 months, it would be an excuse to do the 5spd converson. What do the "kits" offer that a custom setup doesn't that would keep from killing the tranny?

Mad-MAX_SE

iTrader: (2)

nothing...stock auto's just don't like that kind of prolonged stress. It causes alot of heat to build up in th fluid and will fry the clutch packs. Even with a VB recalibration (mod) with new selenoids and a tranny cooler, it's still not going to last if you go too far north of 250hp. You might get your 10-12 months out of it, but it is honestly a waste of money. I would wait till your budget can take the effects of what can happen after the turbo goes in, rather than just enough to get it put in. there's always something that'll creep out of the wood work when you least expect it.

Since you mention the conversion, i would do that first and save yourself the headache later. besides, by the time you save up to get it all installed and tuned correctly, you'll be much more proficient driving the stick.

Sorry if i got way off track, but think outside the box... i would listen to what the turbo guys tell you (Bags, Shadow, Redmax, Hal, Mardi....), since they obviously have the experience you're trying to learn from.

HomerMAC

iTrader: (5)

how about super charger.. how is that on the trannny.. the vortec charger...

Bags

iTrader: (3)

With the Turbo you have more TQ on the tranny. And it's exactly what mad-max said, the auto is not built for it.

I had ~250 whp and broke my auto in less than 6 months. I had a STG2 vb and a tranny cooler.

And you'll have ~$2k in 6 months?

And Redmax IS THE MAN for a built auto. He had one.

I just went to a 5spd with a better clutch and flywheel.

Also, the Auto is LARGER than the 5 spd, so your down pipe will either need to be smaller or VERY close to the tranny.

AVOID THE HEADACHE.

chris'smax

iTrader: (3)

Why is it that the turbo is more harsh on the auto than the SC? Is it because you reach peak boost at a lower RPM which causes the tranny to handel more power throughout the RPM band? Just wondering.

Also bigleman, I have the SC setup w/3.125 pulley on my auto. I haven't had any trouble yet(knock on wood) but i drive like a grandma most of the time

bigleman

iTrader: (4)

thank you all for the great replies, even though that wasnt what i wanted to hear

And I guess youre right about learning the stick. I'm sure the Maxima is much more different compaired to a Jeep. I guess thats the way I'm gonna have to go, cause I really dont plan on putting an extra 2 grand into the auto when I was planning on converting later on down the road anyway.

Oh and about the auto tranny being bigger and in the way, i found a setup on Hal's site that looks like it would work. I think I heard it called a forward y-pipe or something. But your right, it would be easier to do on the 5spd.

Thanks agian for the good replies, if anyone else has any info to share, please chime in!

Shadow

iTrader: (15)

Stock tranny is still surviving in my car...Had the SC for 12 months at 9psi, never dynoed it. Right now, it's holding up to 7 psi on the turbo and 312 lb/ft at the wheels. Made about 25 1/4 mile passes on it, and countless dyno pulls. Original tranny with 104K on it.

Turboing and auto is not much different than a turbo on a 5 spd. Only difference is ground clearance, I don't have any. I will be making a few changes soon that should free up another inch of so which would be great.

Car is down right now becuase the alternator went out. New one is going in around Thanksgiving, soon as I get a free minute. Then we're going to install the J30 MAF and take the boost up. I'm hoping to see 400whp on the turbo alone, then we'll spray it.

Nealoc187

iTrader: (23)

A turbo, given the same "peak boost" puts out a ton more power than the same boost on with an engine driven supercharger that only reaches that peak boost at the very end of the rpm band. That is why a 10psi turbocharged car is so much faster than a 10psi supercharged car, it's putting down alot more power for a longer period of time throughout the powerband. In addition to that, often a turbo's power comes on very suddenly, whereas a supercharger builds boost gradually from idle to redline. A turbocharger may go from no boost to peak boost in only a 1000rpm span.

bigleman

iTrader: (4)

Hey shadow, when are you guys releasing the turbo kit?

chris'smax

iTrader: (3)

Thats what i thought so therefore the tranny is under abuse for a longer period

chris'smax

iTrader: (3)

That makes me feel alot better when i hear positive stories about auto's boosted. I guess you drive pretty conservative also?

Bags

iTrader: (3)

When there are more blown auto trannies from turbos than working auto trannies in turbo's, it should be a sign.

And once again, SC'D power IS different than turbo power

20th maxstyle

iTrader: (4)

I've been though 3 autos. I doin a swap as we speak.

Oblongshapes

iTrader: (1)

When I turbo, (daily driver boost at 6-7psi) will my freshly rebuilt tranny with an exedy stage 1 clutch hold up?

turbo97SE

iTrader: (3)

We'd thought about doing an auto kit but people would lose maybe 3 inches of ground clearance. We have done one custom auto that loses no ground clearance at all but that requires replacing an engine mount and install was not so easy. If you don't have the budget to do it right, don't do it ... auto transmissions, while cheap can quickly add up. Don't know much about autos but if you have poor traction and open diff, you may get away with high hp and tq, since it is less stress on the transmission overall, but you have no tracton! Best way to do turbo kit on an auto is to do a 5 speed swap first!

Aaron92SE

iTrader: (128)

With all these auto trannies that died, why did they die? How hot did the fluid get? Did they have a VB mod? Just curious what the #1 cause of tranny failure is when you put that much power through it.

There have been a lot of automatics out there doing 300fwhp and they are all fine. Just make sure you keep the fluid temps down and quicken those shifts. Thanks.

Bags

iTrader: (3)

I'll post up later, but dixit and I both had VB mods and tranny coolers.



Again, there is a LARGE difference between SC power and TC power.

Aaron92SE

iTrader: (128)

Ok thanks. I know a turbo will produce more power than a SC at the same psi. But, lets say one auto has 250fwhp with turbo and one SC has 250fwhp. Since the power curves will be so different from one another, one will obviously be faster in the 1/4 mile. But, if we try to get them as close together as possible, for comparison reasons, why would the turbo cause the auto tranny to die much faster than if it was SC'd with the same power.

I understand that the power can come on much more suddenly than a SC. But, how is this any different than someone spraying nitrous? I know nitrous isn't sprayed at every stoplight, but you aren't above 4K rpm at every stoplight either if you had turbo.

Any info would be greatly appreciated.

Bags

iTrader: (3)

Well more power might be the wrong way to say it. Boost will peak sooner, or it should, since SC makes peak boost @ redline.

And for this discussion we will say the Turbo makes peak boost @ 4000 rpm. So at redline/6500 rpm when the auto shifts, your @ peak boost. Now you land above 4000rpm/peak boost and just about peak WTQ. And we know there is more WTQ in the Turbo car (guven equal setups), cause there is more boost at PEAK Volumetric Effciency.

So your causing more friction and heat with the increased WTQ.

And normal driving is not much of a problem. When you start driving a little harder and your tranny is shifting under part throttle while boosting, the shift is not as hard as the WOT shift. I started noticing the tranny slipping under ~4-5 psi and at part throttle.

HARD driving is a slightly less harsh, the TCM says hard shift and the VB is ready for it and built for it.


This is mostly my reasoning, if you find any flaws tell me, I may be incorrect or confused.

Aaron92SE

iTrader: (128)

Thanks for your help. Since you've been there and done that, I am trying to heed every word you say. I understand that if you stay under boost, you are able to drive around town just fine. But with the turbo I am looking at (t3 .63 A/R turbine with t04E .60 A/R and .50 - .57 trim) I should be able to make some boost at 2500 rpm, right off the line. That's my plan.

With my VB mod (Max Tuning stage 2), I notice that my shifts are just as firm at 4K rpm than at 6700 rpm (redline). I am talking about the actual shift. I understand that since I have more power going to the wheels at 6700, my shifts will seem faster. But as far as how quick the shift is, I believe it's just as fast at lower rpm than at upper rpm.

But the only reason I can see that my tranny can die faster is due to more sudden surges of power. If I am hard on my car (which I KNOW I will be), I will be making boost at every stoplight. And those sudden surges of power will start taking a toll on my weak 155K mile tranny. It will be like spraying nitrous at every stoplight. That is my idea why turbo seems to kill trannies faster than SC. As said above, SC makes less boost at lower rpm and the sudden surge of power isn't nowhere near what it is with a turbo.

Also, how many 14 second SC'd Maximas have you seen? A LOT! How many 14 second turbo maximas have you seen? None that I can think of. Simply put, a turbo will make more power easier. The more power you put thru your tranny, the quicker it will die.

I am also looking into my options for building a beefier tranny. I need to first find the parts that I will need so I will be able to put 300fwhp through the tranny. I also need to find a reputable tranny shop in FL. If I can't find anything, I might be forced to get Maximum Tuning ship me a tranny.

I have been heavily studying turbo setups for the past 6 months. The more I can learn, the better off I will be when I start piecing together my turbo setup. I want to know my entire setup before I start buying parts.

I hope we can keep this thread alive b/c so far, there is some great info in it.

Bags

iTrader: (3)

BTW I ran ~14.6x @ 101.xx @ 7 psi... so I am in the 14's. I posted in the 1/4 forum. I have not been back since I am @ 10 psi now.

Aaron92SE

iTrader: (128)

I have a 93mph trap speed. You see how much more power you have? THat 101mph trap speed is mid 13s easily if you can get atleast a 2.20 60'. Did you have traction problems? Or did your turbo really lag that bad? I know you had some serious problems with turbo lag on your old and busted turbo. But was your car running well when you ran the 1/4 mile?